How to have two parallel emacs environments?

How to have two parallel emacs environments?

[Guido Van Hoecke]

Hi,

I would like to reorganise and actualise my emacs current setup files.

To facilitate this time consuming and laborious process I would really
like to experiment in a temporary second emacs environment which would
gradually be extended to eventually provide at least the support
currently provided by my official setup.

I was hoping that I could start an alternate emacs using the -u option so
that I could get a separate instance using the growing new setup file.
But obviously that does not work as it expects a user name, not an init
file path.

Is there any way to launch an emacs with a specific init file?

Or is there a different approach to this problem?

Thanks in advance for your suggestions and ideas,


Guido

--
The story you are about to hear is true.
Only the names have been changed to protect the innocent.

Re: How to have two parallel emacs environments?

[Michael Heerdegen]

Guido Van Hoecke <guivho@gmail.com> writes:

> Is there any way to launch an emacs with a specific init file?

I would do emacs -q -l /path/to/init-file

It's not exactly the same as specifying an init file but should do the
job.

Michael.

Re: How to have two parallel emacs environments?

[Guido Van Hoecke]

Hi Michael,

On 24 March 2014 23:54, Michael Heerdegen <michael_heerdegen@web.de> wrote:
> Guido Van Hoecke <guivho@gmail.com> writes:
>
>> Is there any way to launch an emacs with a specific init file?
>
> I would do emacs -q -l /path/to/init-file
>
> It's not exactly the same as specifying an init file but should do the
> job.

It does indeed, thanks a lot!

Guido

Re: How to have two parallel emacs environments?

[Luca Ferrari]

On Mon, Mar 24, 2014 at 11:54 PM, Michael Heerdegen
<michael_heerdegen@web.de> wrote:
> Guido Van Hoecke <guivho@gmail.com> writes:
>
>> Is there any way to launch an emacs with a specific init file?
>
> I would do emacs -q -l /path/to/init-file
>

Also the -u option could be an option to specify a per-user init file.
Or specifying a switch-function to call on startup in order to
configure the whole editor differently?

Luca

Re: How to have two parallel emacs environments?

[Pascal J. Bourguignon]

Luca Ferrari <fluca1978@infinito.it> writes:

> On Mon, Mar 24, 2014 at 11:54 PM, Michael Heerdegen
> <michael_heerdegen@web.de> wrote:
>> Guido Van Hoecke <guivho@gmail.com> writes:
>>
>>> Is there any way to launch an emacs with a specific init file?
>>
>> I would do emacs -q -l /path/to/init-file
>>
>
> Also the -u option could be an option to specify a per-user init file.
> Or specifying a switch-function to call on startup in order to
> configure the whole editor differently?


If you load different configurations from ~/.emacs, you may want to set
custom-file to tell emacs where to store the customizations.

For example, I have this in my ~/.emacs:

;; […]
(let ((configuration (find-configuration (hostname))))
  (if configuration
      (let ((file (file-truename (cdr configuration))))
        (load file)
        ;; setting custom-file needs to be done after we've customized our stuff
        ;; otherwise it may be overridden with an empty customization.
        (setq custom-file (or file custom-file)))
      (message "Found no configuration to load for %s" (hostname))))


-- 
__Pascal Bourguignon__
http://www.informatimago.com/
"Le mercure monte ?  C'est le moment d'acheter !"

Re: How to have two parallel emacs environments?

[Guido Van Hoecke]

Hi Pacal,

"Pascal J. Bourguignon" <pjb@informatimago.com> writes:

> Luca Ferrari <fluca1978@infinito.it> writes:
>
>> On Mon, Mar 24, 2014 at 11:54 PM, Michael Heerdegen
>> <michael_heerdegen@web.de> wrote:
>>> Guido Van Hoecke <guivho@gmail.com> writes:
>>>
>>>> Is there any way to launch an emacs with a specific init file?
>>>
>>> I would do emacs -q -l /path/to/init-file
>>>
>>
>> Also the -u option could be an option to specify a per-user init file.
>> Or specifying a switch-function to call on startup in order to
>> configure the whole editor differently?
>
>
> If you load different configurations from ~/.emacs, you may want to set
> custom-file to tell emacs where to store the customizations.
>
> For example, I have this in my ~/.emacs:
>
> ;; […]
> (let ((configuration (find-configuration (hostname))))
>   (if configuration
>       (let ((file (file-truename (cdr configuration))))
>         (load file)
>         ;; setting custom-file needs to be done after we've customized our stuff
>         ;; otherwise it may be overridden with an empty customization.
>         (setq custom-file (or file custom-file)))
>       (message "Found no configuration to load for %s" (hostname))))

One more for my setup files :)

Thanks.


Guido

--
Laughter is the closest distance between two people.
		-- Victor Borge

Re: How to have two parallel emacs environments?

[Nicolas Richard]

Hello,

Guido Van Hoecke <guivho@gmail.com> writes:
> I was hoping that I could start an alternate emacs using the -u option so
> that I could get a separate instance using the growing new setup file.

You can start emacs with a modified HOME variable~:
HOME=/tmp/a-new-home emacs

Then emacs will look for /tmp/a-new-home/.emacs. One advantage is that
the package initialization happens normally. One advantage or
disadvantage (depending on your POV) is be that if you refer to files
relative to ~/ in /tmp/a-new-home/.emacs, they'll in fact be relative to
/tmp/a-new-home and not /home/yourusername/

-- 
Nico.

Re: How to have two parallel emacs environments?

[Guido Van Hoecke]

Hi Nicolas,

Nicolas Richard <theonewiththeevillook@yahoo.fr> writes:

> Hello,
>
> Guido Van Hoecke <guivho@gmail.com> writes:
>> I was hoping that I could start an alternate emacs using the -u option so
>> that I could get a separate instance using the growing new setup file.
>
> You can start emacs with a modified HOME variable~:
> HOME=/tmp/a-new-home emacs
>
> Then emacs will look for /tmp/a-new-home/.emacs. One advantage is that
> the package initialization happens normally. One advantage or
> disadvantage (depending on your POV) is be that if you refer to files
> relative to ~/ in /tmp/a-new-home/.emacs, they'll in fact be relative to
> /tmp/a-new-home and not /home/yourusername/

That's a clever way to solve the problem. The ~ problem neds to be taken
into account but that's easily solvable.

Thanks for the suggestion :)


Guido

--
Thus spake the master programmer:
	"When program is being tested, it is too late to make design changes."
		-- Geoffrey James, "The Tao of Programming"

Re: How to have two parallel emacs environments?

[Luca Ferrari]

There is also a org-dotemacs module on Melpa that allows to tag parts
of the init file to load on startup. I've never tried it, but could be
another option (even if I think it's a bit too complex for this
specific problem).

Luca

Re: How to have two parallel emacs environments?

[Guido Van Hoecke]

Hi Luca,

Luca Ferrari <fluca1978@gmail.com> writes:

> There is also a org-dotemacs module on Melpa that allows to tag parts
> of the init file to load on startup. I've never tried it, but could be
> another option (even if I think it's a bit too complex for this
> specific problem).

Since my original posting, I have switched to a slightly reworked init
file, tangled from my emacs-guivho.org. Still needs a lot of work, so it
might well be worth looking into org-dotemacs :)

Thanks for the suggestion,


Guido

--
Weinberg's First Law:
	Progress is only made on alternate Fridays.